Car Battery

Ok i bought this 600 watt car amp for a cheap price i connected all the wiring correctly and the first time i did it it worked but i didnt have a good ground at the time but it still worked. when i was driving all of a sudden the car amp went into protection mode. when i got home i played around with the ground wire and it would come on and off so i thought it was the ground. i k off all wiring and then connected the ground better and rewired e thing. now the car amp is in protection mode and i cant get it out. ive also noticed that when i take the battery cord off the amp the car amp protection mode is still on should it be off?another thing is when all the wiring is connected right i can hear a faint thump in myspeakers like its trying to connect all my fuses are good and the wiring is good i am puzzled and confused and i hope i can get some info

My friend, i have never enjoyed hearing someone getting ripped off by buying a cheap amp. unfortunately, it sounds as if your amp may have had it. even if it is rockford fosgate, or jbl, when an amplifier does that noise, it typicallly means $60-$100 worth of repair. i do alot of car audio, and an amplifier doesnt make that noise unless it is getting radio interferance during it is route. unplug the rca cables from the amplifier and then turn it on. if it still makes your speakers hum or, in the case of subwoofers, thump @ 60hz, it means your amp is fried. it is always a wise decision to purchase audio equipment after a little looking around. buying a quality 600 watt rms amplifier for $300 is always better than buying three cheap 600 watt max amps for $500, always.